U.S. Pat. No. 5,563,175 and its family relate to compounds that are analogs of glutamic acid and gamma-aminobutyric acid (GABA). 
wherein R1 is a straight or branched alkyl group having from 1 to 6 carbons, phenyl, or cycloalkyl having from 3 to 6 carbons, R2 is hydrogen or methyl; and R3 is hydrogen, methyl, or carboxyl. The compounds are useful in antiseizure therapy and for CNS disorders such as epilepsy, Huntington""s Chorea, cerebral ischemia, Parkinsonism, tardive dyskinesia, and spasticity. The compounds are recited as also possibly useful as antidepressants, anxiolytics, and antipsychotics.
U.S. Pat. No. 6,001,876 covers the compounds of Formula I above in the treatment of pain.
U.S. patent application Ser. No. 60/050736 covers the compounds of Formula I above in the treatment of inflammation.
U.S. patent application Ser. Nos. 60/056753 and 60/074794 cover the compounds of Formula I above in the prevention and treatment of gastrointestinal damage such as inflammatory bowel disorders (IBD) and inflammatory bowel disorder (IBD).
U.S. patent application Ser. No. 60/072397 covers the compounds of Formula I above in the treatment of skeletal and muscular pain.
There is no disclosure in the above to make obvious the present invention of the uses of the compounds of Formula I in the treatment of mania and bipolar disorder.
U.S. Pat. Nos. 4,024,175 and 4,087,544 teach cyclic amino acids of formula 
wherein R1 is hydrogen or lower alkyl and n is an integer of from 4 to 6 and the pharmaceutically acceptable salts thereof.
The compounds disclosed in the above United States patents are useful for the therapy of certain cerebral diseases, for example, they can be used for the treatment of certain forms of epilepsy, faintness attacks, hypokinesia, and cranial traumas. Additionally, they bring about an improvement of cerebral functions and thus are useful in treating geriatric patients. Particularly valuable is 1-(aminomethyl)-cyclohexane-acetic acid (gabapentin).
U.S. Pat. No. 5,084,479 teaches the compounds of the above formula for therapeutic use in neurodegenerative disorders such as Alzheimer""s, Huntington""s, Parkinson""s, and Amyotrophic Lateral Sclerosis. It also teaches the use of the compounds in the treatment of acute brain injury such as stroke, head trauma, and asphyxia.
U.S. Pat. No. 5,025,035 teaches the use of the compounds of the above formula for depression.
U.S. Pat. patent application Ser. No. 08/281285 (now abandoned) teaches the use of the compounds of the above formula to treat anxiety and/or panic disorders.
The present invention relates to novel therapeutic uses of a known compound, pregabalin, its derivatives, and pharmaceutically acceptable salts. Pregabalin is (S)-3-(aminomethyl)-5-methylhexanoic acid. The invention concerns a method for treating the symptoms of mania in a human in need of such treatment. This method includes, but is not limited to the treatment of mania in all its various forms whether acute or chronic, single or recurrent episode, and associated with depression or not. The invention further includes the preventive treatment of bipolar disorder in persons predisposed to this disorder.
Episodes of acute mania are characterized by elevated or irritable mood, disturbed sleep, grandiosity, increased motor activity, pressured thinking, distractibility and poor concentration, impaired judgment, and sometimes psychotic symptoms. The irritability can lead to outbursts of angry or aggressive behavior. Often the episodes are preceded by a period of disturbed sleep. The distractibility makes the patient move endlessly from one activity to another often to the detriment of their physical, occupational, and social well-being. The impact of these behaviors is further aggravated by the lapses of judgment and poor decision-making that is characteristic of this illness.
Episodes of mania occur in patients who suffer from bipolar disorder which is an illness characterized by alternating cycles of depression and mania. This disorder is distinct from the more common form of depression, called Major Depressive Disorder, in which patients only experience recurrent episodes of depression but no mania. Bipolar disorder can be diagnosed by the clinical evaluation of patients using the criteria specified in the Diagnostic and Statistical Manual (DSM-IV) of the American Psychiatric Association. In this nomenclature system, bipolar disorder is subsumed under the broader class of Mood Disorders and is clearly distinguished from the Anxiety Disorders and from Organic Mental Disorders.
In studies of healthy subjects and patients suffering from anxiety, pregabalin has been noted to induce sedative and calming effects. These effects will be beneficial in the symptomatic treatment of patients suffering from mania who exhibit irritability, distractibility, and poor judgment. This is a novel use for pregabalin which would not be obvious to a medical practitioner of ordinary skill.
Pregabalin has also been found to enhance sleep. This effect will be beneficial in acute mania and will also lead to reducing the risk for onset of a new episode of mania in a predisposed individual. Thus, the prophylactic use of pregabalin for bipolar disorder is also taught.